A project's skin refers to the appearance of a project's playback controls, border, and table of contents. You can customize the appearance and layout of these to change the appearance and functionality of your project.
As you can see, you can toggle visibility of the playback controls entirely, hide it during quizzes, and choose whether it overlays the project or not.
You can also choose a design theme for the playback controls bar, or just edit the colors on your own.
Next, you can control the position and layout of the controls bar using these menus.